Long-term follow-up of de novo allergy in pediatric liver transplantation--10 yr experience of a single center.

We conducted a study to clarify the incidence, clinical course, and risk factors of de novo allergies after liver transplantation. Ninety-three patients who had been followed longer than one yr and who had no previous allergy history were included. Forty-two patients (45.2%) developed de novo allergy. Of them, food allergy developed in 35 (37.6%). Respiratory allergy was observed in three (3.2%), and a patient (1.1%) had drug allergy. Fifty-two (55.9%) of the 93 patients developed eosinophilia. The median age of patients with de novo allergy was 15 months (IR 11.3-20 months). De novo allergy developed five months after liver transplantation (IR 2.3-9.5 months) and lasted for 16 months (IR 8-34.5 months). Younger age at liver transplantation displayed statistically significant differences in development of allergy between allergy and non-allergy groups. Twenty-nine (69.0%) patients improved from allergy during the follow-up period. No patient with de novo gastrointestinal allergy progressed to any respiratory allergy such as asthma. Older age at transplantation, EBV non-risk, and CMV non-risk had statistical significance in allergy improvement. Younger age at transplant predisposes to the development of allergy, while improvement of allergy is achieved more in older age.